A high field mössbauer study of nickel—zinc ferrites

Abstract

The Mössbauer effect has been used to study five specimens of the disordered system Ni1–xZnxFe2O4 for 0.6 ≤ x ≤ 0.95 in applied magnetic fields of 5 and 9T. The spectra have been analysed in terms of a single hyperfine field resulting from A site Fe ions and several fields due to B site Fe ions. It is shown that some of the B site ions have their spin moments reversed at high Zn concentrations. The cation distribution is shown to follow the formula (ZnxFe1–x) (Fe1+xNi1–x)O4. The A site Fe magnetic moments are found to be collinear with large applied magnetic fields, whereas all the B site moments exhibit some degree of canting. The B site canting angles are found to increase with Zn concentration. Increasing the applied magnetic field decreases the canting angles of the normal B site ions for all the specimens studied.